Chapter Two Voltage and Current Measurement CONTINUE بسم الله الرحمن الرحيم 10/6/20151A. Prof. Magdi El-Saadawi

2.4. Current Measurement Current measuring devices are selected for:  Precision  Stability  Frequency response, including dc  Galvanic isolation التأكد من العزل التام بعدم مرور تيار  Presentation of the data  Effect on measured circuit 10/6/2015A. Prof. Magdi El-Saadawi2

Using an Ammeter as a Voltmeter and vice versa 10/6/20153A. Prof. Magdi El-Saadawi

Using a Voltmeter as an Ammeter By using a shunt resistance to reduce the large internal resistance of the voltmeter, so that it can be connected in series in the circuit 10/6/2015A. Prof. Magdi El-Saadawi4

Using an Ammeter as a Voltmeter By using a series resistance to enlarge the small internal resistance of the ammeter, so that it can be connected in parallel in the circuit 10/6/2015A. Prof. Magdi El-Saadawi5

Figure 2.34 Changing the range of a Voltmeter using a number of high resistance resistors connected in series with meter coil and known as multiplier 10/6/2015A. Prof. Magdi El-Saadawi6

Figure 2.35 Changing the range of a Ammeter using a number of low resistance resistors connected in parallel with meter operating coil and known as multiplier 10/6/2015A. Prof. Magdi El-Saadawi7

10/6/2015A. Prof. Magdi El-Saadawi8

10/6/2015A. Prof. Magdi El-Saadawi9 Solution

10/6/2015A. Prof. Magdi El-Saadawi10 Solution guide

The Moving Magnet Meter 10/6/2015A. Prof. Magdi El-Saadawi11

The D’Arsonval Meter 10/6/2015A. Prof. Magdi El-Saadawi12

The Electrodynamometer 10/6/2015A. Prof. Magdi El-Saadawi13

The RF Ammeter and True rms 10/6/2015A. Prof. Magdi El-Saadawi14

The Current Transformer 10/6/2015A. Prof. Magdi El-Saadawi15

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Current and potential transformers for High voltage measurements 10/6/2015A. Prof. Magdi El-Saadawi17